US5026748A - Thermally conductive adhesive - Google Patents

Thermally conductive adhesive Download PDF

Info

Publication number
US5026748A
US5026748A US07/520,286 US52028690A US5026748A US 5026748 A US5026748 A US 5026748A US 52028690 A US52028690 A US 52028690A US 5026748 A US5026748 A US 5026748A
Authority
US
United States
Prior art keywords
adhesive
film
thermal
fibers
filled
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US07/520,286
Inventor
Jerome T. Adams
Bruce A. Yost
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fiberite Inc
Original Assignee
EI Du Pont de Nemours and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by EI Du Pont de Nemours and Co filed Critical EI Du Pont de Nemours and Co
Priority to US07/520,286 priority Critical patent/US5026748A/en
Assigned to E. I. DU PONT DE NEMOURS AND COMPANY, A CORP. OF DE. reassignment E. I. DU PONT DE NEMOURS AND COMPANY, A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ADAMS, JEROME T., YOST, BRUCE A.
Priority to IL9795791A priority patent/IL97957A/en
Priority to AU76137/91A priority patent/AU629157B2/en
Priority to JP3128213A priority patent/JPH06212137A/en
Priority to AT91304030T priority patent/ATE128168T1/en
Priority to EP91304030A priority patent/EP0456428B1/en
Priority to CA002041807A priority patent/CA2041807A1/en
Priority to ES91304030T priority patent/ES2078443T3/en
Priority to DE69113108T priority patent/DE69113108T2/en
Priority to MX025667A priority patent/MX172824B/en
Priority to TR91/0473A priority patent/TR25806A/en
Priority to SU914895345A priority patent/RU2052483C1/en
Priority to CN91103592A priority patent/CN1041743C/en
Priority to KR1019910007335A priority patent/KR910020139A/en
Priority to BR919101849A priority patent/BR9101849A/en
Publication of US5026748A publication Critical patent/US5026748A/en
Application granted granted Critical
Assigned to FIBERITE, INC., A DELAWARE CORP. reassignment FIBERITE, INC., A DELAWARE CORP. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: E.I. DU PONT DE NEMOURS AND COMPANY, A DELAWARE CORP.
Assigned to FIBERITE, INC., A DELAWARE CORPORATION reassignment FIBERITE, INC., A DELAWARE CORPORATION SEE RECORDING AT REEL 8621, FRAME 0594. Assignors: E.I. DU PONT DE NEMOURS AND COMPANY
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
    • H05K3/303—Surface mounted components, e.g. affixing before soldering, aligning means, spacing means
    • H05K3/305—Affixing by adhesive
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J9/00—Adhesives characterised by their physical nature or the effects produced, e.g. glue sticks
    • C09J9/02—Electrically-conducting adhesives
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J201/00—Adhesives based on unspecified macromolecular compounds
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
    • H01L23/482—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of lead-in layers inseparably applied to the semiconductor body
    • H01L23/4827—Materials
    • H01L23/4828—Conductive organic material or pastes, e.g. conductive adhesives, inks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/48—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
    • H01L23/488—Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor consisting of soldered or bonded constructions
    • H01L23/498—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers
    • H01L23/49866—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers characterised by the materials
    • H01L23/49883—Leads, i.e. metallisations or lead-frames on insulating substrates, e.g. chip carriers characterised by the materials the conductive materials containing organic materials or pastes, e.g. for thick films
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
    • C08L2666/54—Inorganic substances
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31—Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32—Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321—Disposition
    • H01L2224/32151—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32225—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/0201—Thermal arrangements, e.g. for cooling, heating or preventing overheating
    • H05K1/0203—Cooling of mounted components
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/02—Fillers; Particles; Fibers; Reinforcement materials
    • H05K2201/0203—Fillers and particles
    • H05K2201/0206—Materials
    • H05K2201/0209—Inorganic, non-metallic particles
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/02—Fillers; Particles; Fibers; Reinforcement materials
    • H05K2201/0275—Fibers and reinforcement materials
    • H05K2201/0281—Conductive fibers
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/03—Conductive materials
    • H05K2201/032—Materials
    • H05K2201/0323—Carbon
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • This invention relates to thermally conductive adhesives and, more particularly, it relates to an adhesive matrix filled with a three-dimensional arrangement of mesophase pitch based carbon fibers.
  • Thermal management in electronic packaging has always been an important design consideration, and it is even more so today because packaging density (and hence heat dissipation) is increasing dramatically. More powerful and closer spaced chips, finer grid patterns, and surface mount devices such as leadless ceramic chip carriers need materials exhibiting high thermal conductivities and/or tailorable coefficients of thermal) expansions (CTE), so that heat removal is efficient and/or CTE mismatches between components are reduced. Facilitating heat removal and reducing CTE mismatches are very desirable attributes for they lead to more flexible packaging design, improved operating performance, and increased life expectancy (through reduced failures).
  • CTE thermal conductivities and/or tailorable coefficients of thermal) expansions
  • Thermally conductive, tailorable CTE organic-based adhesives play an important role in thermal management in electronic packaging. They are used for a variety of applications, including:
  • chip bonding to chip carriers, substrates or heat sinks
  • resistor, capacitor, diode, etc. attachment i.e. using fillet adhesives
  • these adhesives are filled with metallic fillers such as silver or inorganic fillers such as alumina or boron nitride.
  • metallic fillers such as silver or inorganic fillers such as alumina or boron nitride.
  • Alumina fillers which are electrically insulating, increase the thermal conductivity of the base polymer approximately 3-5 ⁇ , based on the filler loading, geometry and size.
  • Silver flakes are used when maximum thermal conductivity and electrical conductivity are required, as it too increases the thermal conductivity of the base polymer approximately 3-5 ⁇ , depending on the loading. All of these fillers have several drawbacks, however. High weight percentages of silver are required (e.g. 79 wt. % is used in some adhesives to achieve the desired performance levels), and since silver is expensive, the cost of these fillers becomes substantial.
  • Silver Similar to silver, high weight percentages of inorganic fillers are also required and are relatively expensive as well. Silver also suffers from a phenomena referred to as metallic electromigration; an article by S. Krumbein (IEEE Transactions on Components, Hybrids, and Manufacturing Technology, Vol. 11, No. 1, Mar. 1988) describes metal migration in more detail.
  • An adhesive material has been developed to complement the move toward thermal management in electronic packaging which exhibits a cost effective combination of needed properties including high thermal conductivities, uniform in-plane CTE's, low density and high stiffness.
  • This material comprises an adhesive filled with from about 20 to about 60 weight percent of three-dimensional structure of mesophase pitch based carbon fibers.
  • the carbon fibers are of variable length and variable width.
  • Preferably the fibers have a length to width ratio greater than 10 and the fibers have a distribution of width of from about 1 to about 10 micrometers.
  • Suitable adhesive resins are synthetic adhesives such as thermosetting, thermoplastic, elastomeric or combinations of these types.
  • the fibers would be added as uniformly as possible and the components would be mixed to give a homogeneous blend. This methodology would help ensure fiber encapsulation and promote film uniformity and homogeneity.
  • the rheology would be closely controlled by varying the chemistry of the resin and the amount of fiber that is added.
  • the homogeneous blend would be cast using film-casting equipment.
  • FIG. 1 is a schematic cross sectioned elevation view of a general electronic packaging arrangement in which the thermally conductive adhesives of this invention are useful.
  • FIG. 2 is a photomicrograph of an adhesive layer of this invention.
  • FIG. 2a is a vector diagram representative of three dimensional fiber placement in the adhesive layer of FIG. 2.
  • the structure 10 shown is referred to broadly as an electronic packaging system that includes as component parts a base 12 carrying a plurality of pins 13 and having a cavity 14 covered by a lid 16. Within cavity 14 is a die or a chip 18 that is adhered to a heat sink 20 by means of thermal adhesive layer 22. A similar thermal adhesive layer 22 seals lid 16 to the base 12 and the base 12 to a printed wiring board 24.
  • Example 3 28 volume percent fibers
  • FIG. 2 A structure showing a resin filled with a three-dimensional fiber structure with fibers of varying lengths and widths is observed. More particularly, fibers 30 are oriented in-plane in the x direction, fibers 32 are oriented in-plane in the y direction; and fibers 34 are oriented out-of-plane or through-the-thickness in the z direction.
  • Thermal conductivity is measured in accordance with the following methods and is designated as (BTU)(in)/(hr)(ft 2 )(°F.):
  • the film is placed on an aluminum surface which is held at a temperature of about 40° C.
  • An aluminum cylinder of known properties and equipped with a thermocouple, is held at room temperature ( ⁇ 25° C.) before being placed on top of the film sample.
  • the temperature rise of the aluminum cylinder is monitored and subsequently analyzed to obtain the thermal resistance of the film and the film/aluminum interfaces.
  • At least four layers of film are added sequentially to establish a relationship between thermal resistance and film thickness, from which the film thermal conductivity can be determined because compensation can then be made for the film/aluminum interface resistances. Pressure is applied to the "stacks" to minimize interface thermal resistances.
  • the sample is placed between two copper-surfaced plates controlled at different temperatures Surrounding the sample is a guard heater maintained at or near the mean sample temperature to minimize lateral heat transfer.
  • the heat flux between the two plates is measured with a heat flux transducer attached to one of the plates.
  • the overall temperature difference between the two plates surfaces is measured with built-in thermocouples.
  • a thin layer of a commercially available heat sink compound (such as Dow Corning 340) is usually applied to the sample and the test is run under external pressure. Knowing the sample thickness, the plate surface temperatures, the measured heat flux and the contact thermal resistance, the thermal conductivity of the sample can be determined.
  • the Dynatech C-Matic tester is not particularly suited for very thin materials (i.e. with thicknesses less than 0.040"). Therefore, a guarded heat flow method and apparatus to measure through-the-thickness thermal conductivities of thin films has been developed.
  • the device consists of two copper rods, approximately 1" in diameter and 2" in length. Embedded along the length of each rod are two thermocouples, spaced 1" apart. The rods are wrapped in fiberglass insulation to prevent lateral heat loss.
  • the film sample coated with "Nujol” mineral oil, is placed between an end of each of the copper rods (which also have a coat of oil) to form a rod/film/rod stack. (The oil is present to ensure good heat transfer between the rods and the film).
  • the stack is positioned between two heated press platens (top platen always hotter than the bottom platen), put under a compressive load to minimize interfacial thermal resistances, and wrapped with another layer of insulation.
  • the stack is allowed to reach equilibrium and the resultant temperature profiles across the copper rods are recorded.
  • the experiment is repeated with different platen set-point temperatures and stack pressures.
  • the thermal conductivity of the film can be calculated.
  • Ciba-Geigy hardener HT9679 and 12.5 grams of Ciba-Geigy hardener HT939 were added to a mixture of 60 grams of Dow Chemical "Quatrex" 1010 resin, 160 grams of Dow Chemical "Quatrex” 2010 and 180 grams of Union Carbide ERL-4206 resin. The resulting mixture was stirred until uniform. 40 grams of a three dimensional structure of mesophase pitch based carbon fiber were added to 60 grams of the resulting mixture to form a 40 weight % fiber reinforced epoxy resin. This filled mixture was passed through a 3 roll mill five times and cast onto a 5 mil thick silicone coated polyester film using a spatula. After curing at 160° C. for 1 hour, the filled adhesive film was removed from the polyester film and was polished using 500 and 1200 grit paper.
  • the polished film was tested for through-the-thickness thermal conductivity using the Guarded Heat Flow: Thin Material method.
  • the thermal conductivity of this adhesive listed in Table 1, is at least equivalent to those of 79 weight % silver flake filled Ditac® QL® Ribbon adhesives commercially available from Du Pont, yet the weight percent fibers was only 40%.
  • a three dimensional structure of mesophase pitch based carbon fiber filled films containing 15, 29 and 39 weight % fibers (10, 20 and 28 volume percent fibers, respectively) were prepared as follows.
  • Three separate dry blends of fibers and K copolyimide powder (representing the three fiber loadings) were prepared by placing the required weights of fiber and powder in polyethylene bags, tying the bags off, and then shaking and mixing the blends to make as uniform a mixture as possible.
  • K copolyimide powder is based on pyromellitic dianhydride and a 70/30 (by weight) mixture of 1,3-bis(3-aminophenoxy)benzene and 2-phenyl-1, 4-bis(4-aminophenoxy))benzene. Approximately 600 grams of each blend were prepared.
  • the pieces of film were run through the press two more times (with Kapton® cover sheets which were then removed) but at a speed of 1 foot/minute to further reduce film thickness.
  • the resulting films were approximately 3-4 feet long, 6-8 inches wide, 10-19 mils thick.
  • Unreinforced films were made similarly. The resulting films were approximately 45 feet long, 10 inches wide, 8-14 mils thick.
  • Pieces of the films were tested for in-plane tensile properties and coefficients of thermal expansions, as well as through-the-thickness thermal conductivities. Because thermal conductivity measurements are made using a variety of techniques and methods, the thermal conductivities were measured via four different methods described herein for comparisons and data validations.
  • Table 2 gives the results which indicate that the film properties are a function of fiber loading; as fiber loadings increase, both out-of-plane thermal conductivities and tensile moduli increase while in-plane CTE's decrease.
  • the highest loaded film has a uniform CTE (10 ppm/°C.) near that of alumina (6-8 ppm/°C.), a typical "target CTE" electronic packaging material.
  • the thermal conductivity and modulus of the highest loaded film are at least equivalent and the CTE is 4 ⁇ lower than these silver filled adhesives, yet the fiber loading was only 39% by weight.
  • Two identical 2" ⁇ 2" squares were cut from a pitch fiber reinforced metal matrix composite heat sink constructed of 16 layers of 6063 aluminum reinforced with E-120 continuous pitch fibers.
  • the fiber orientation was [0/90] 4S and the fiber volume fraction was 35%.
  • One surface of each metal matrix square was scraped with a razor blade and cleaned with solvent to remove all surface contaminants.
  • One circuit board square was bonded to a heat sink square using Hysol Aerospace & Industrial Products Division Epoxi-patch clear 0151 two part epoxy adhesive by brushing a well stirred mix on the clean metal surface, placing the circuit board on the adhesive, and curing the laminated sample under minimum ( ⁇ 25 psi) pressure.
  • the other squares were bonded to each other with the same base adhesive but the adhesive had been filled with 25 weight percent of a three-dimensional structure of mesophase pitch based carbon fiber blended in as the two part epoxy was mixed.

Abstract

Adhesive resins are filled with carbon fibers that have a three-dimensional structure. The fibers have variable lengths and widths. The fiber filled adhesive exhibits high thermal conductivity values. Electronic systems having components bonded by a layer of these adhesives resins have high through-the-thickness thermal conductivity.

Description

CROSS REFERENCE TO RELATED APPLICATION
The following application of common assignee contains some common disclosure with that of the present application:
Title: Improved Thermal Conductive Material
Ser. No.: 07/251,1783
Filed: Oct. 3, 1988
BACKGROUND OF THE INVENTION
This invention relates to thermally conductive adhesives and, more particularly, it relates to an adhesive matrix filled with a three-dimensional arrangement of mesophase pitch based carbon fibers.
Thermal management in electronic packaging has always been an important design consideration, and it is even more so today because packaging density (and hence heat dissipation) is increasing dramatically. More powerful and closer spaced chips, finer grid patterns, and surface mount devices such as leadless ceramic chip carriers need materials exhibiting high thermal conductivities and/or tailorable coefficients of thermal) expansions (CTE), so that heat removal is efficient and/or CTE mismatches between components are reduced. Facilitating heat removal and reducing CTE mismatches are very desirable attributes for they lead to more flexible packaging design, improved operating performance, and increased life expectancy (through reduced failures).
Thermally conductive, tailorable CTE organic-based adhesives (in paste or film form) play an important role in thermal management in electronic packaging. They are used for a variety of applications, including:
die (chip) bonding to chip carriers, substrates or heat sinks
chip carrier and substrate attachment to printed wiring boards (PWB)
PWB bonding to heat sinks
heat sink attachment to chassis
lid sealing
resistor, capacitor, diode, etc. attachment (i.e. using fillet adhesives)
Typically these adhesives are filled with metallic fillers such as silver or inorganic fillers such as alumina or boron nitride. Alumina fillers, which are electrically insulating, increase the thermal conductivity of the base polymer approximately 3-5×, based on the filler loading, geometry and size. Silver flakes are used when maximum thermal conductivity and electrical conductivity are required, as it too increases the thermal conductivity of the base polymer approximately 3-5×, depending on the loading. All of these fillers have several drawbacks, however. High weight percentages of silver are required (e.g. 79 wt. % is used in some adhesives to achieve the desired performance levels), and since silver is expensive, the cost of these fillers becomes substantial. Similar to silver, high weight percentages of inorganic fillers are also required and are relatively expensive as well. Silver also suffers from a phenomena referred to as metallic electromigration; an article by S. Krumbein (IEEE Transactions on Components, Hybrids, and Manufacturing Technology, Vol. 11, No. 1, Mar. 1988) describes metal migration in more detail.
It is known to use adhesives filled with carbon fibers for the purpose of making electrical connections in electrical systems bound together by the adhesive.
SUMMARY OF THE INVENTION
An adhesive material has been developed to complement the move toward thermal management in electronic packaging which exhibits a cost effective combination of needed properties including high thermal conductivities, uniform in-plane CTE's, low density and high stiffness. This material comprises an adhesive filled with from about 20 to about 60 weight percent of three-dimensional structure of mesophase pitch based carbon fibers. The carbon fibers are of variable length and variable width. Preferably the fibers have a length to width ratio greater than 10 and the fibers have a distribution of width of from about 1 to about 10 micrometers. These fibers are described in U.S. Pat. No. 4,861,653 which is incorporated herein by reference.
Suitable adhesive resins are synthetic adhesives such as thermosetting, thermoplastic, elastomeric or combinations of these types.
According to the "Adhesives Technology Handbook" (Noyes Publications, 1985), there are four basic types of adhesives: liquids, pastes, tapes and films, and powders or granules. The two most common type of adhesives for structural and electronic applications are pastes and films. To make a three dimensional structure of mesophase pitch based carbon fiber filled paste, the fibers are added as uniformly as possible to the paste and the components are mixed to get a homogeneous blend. The rheology of the filled paste would be closely controlled by varying the chemistry of the paste and the amount of fiber that is added. (Pastes typically have high viscosities).
To make a three dimensional structure of mesophase pitch based carbon fiber filled adhesive film, at least two routes are available. First, if the adhesive resin was in liquid form, the fibers would be added as uniformly as possible and the components would be mixed to give a homogeneous blend. This methodology would help ensure fiber encapsulation and promote film uniformity and homogeneity. As for the pastes, the rheology would be closely controlled by varying the chemistry of the resin and the amount of fiber that is added. To form the adhesive film, the homogeneous blend would be cast using film-casting equipment.
An alternate route would be if the resin is in powder or granule form, such as a thermoplastic resin might be. A three dimensional structure of mesophase pitch based carbon fiber would be added as uniformly as possible and dry blended to give a homogeneous mixture. The homogeneous blend would be cast to form an adhesive film using an extruder and film casting equipment, or what is commonly done is to extrude pellets of the blend and then use the pellets to extrude adhesive film.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic cross sectioned elevation view of a general electronic packaging arrangement in which the thermally conductive adhesives of this invention are useful.
FIG. 2 is a photomicrograph of an adhesive layer of this invention.
FIG. 2a is a vector diagram representative of three dimensional fiber placement in the adhesive layer of FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, the structure 10 shown is referred to broadly as an electronic packaging system that includes as component parts a base 12 carrying a plurality of pins 13 and having a cavity 14 covered by a lid 16. Within cavity 14 is a die or a chip 18 that is adhered to a heat sink 20 by means of thermal adhesive layer 22. A similar thermal adhesive layer 22 seals lid 16 to the base 12 and the base 12 to a printed wiring board 24.
In FIG. 2 the adhesive layer of Example 3 (28 volume percent fibers) is displayed photomicrographically (200×). A structure showing a resin filled with a three-dimensional fiber structure with fibers of varying lengths and widths is observed. More particularly, fibers 30 are oriented in-plane in the x direction, fibers 32 are oriented in-plane in the y direction; and fibers 34 are oriented out-of-plane or through-the-thickness in the z direction.
These broad utility, general purpose adhesives are particularly attractive to the electronic packaging community, where thermal management is always an issue while weight and stiffness can be (such as in avionic systems). They do not suffer from metal migration and they require less weight of filler than incumbent technologies (e.g. silver flakes or alumina fillers) to achieve a desired level of performance. These adhesives can also be used for structural applications (e.g. bonding a composite part to another composite part or bonding a composite part to a piece of metal such as an end fitting), where CTE mismatches must be minimized. In these applications, the filaments' propensity to form ˜3-D reinforced composites may also be advantageous in increasing the interlaminar shear strength of bonded composites through through-the-thickness (out-of-plane) reinforcement.
THERMAL CONDUCTIVITY MEASUREMENTS
Thermal conductivity (TC) is measured in accordance with the following methods and is designated as (BTU)(in)/(hr)(ft2)(°F.):
Laser Flash
This is a transient technique in which the thermal diffusivity of a composite is determined by subjecting one face of the sample to a brief pulse of energy (less than 1 millisecond duration) from an infrared laser and monitoring the temperature rise on the opposite face with an infrared detector. Knowing the time/temperature profile of the back face of the sample and the distance between the two faces, the thermal diffusivity of the composite is calculated. Knowing this value and the density and specific heat of the composite, the thermal conductivity of the sample is calculated by taking the product of these three values.
Thick-Film Integrator
The film is placed on an aluminum surface which is held at a temperature of about 40° C. An aluminum cylinder, of known properties and equipped with a thermocouple, is held at room temperature (˜25° C.) before being placed on top of the film sample. The temperature rise of the aluminum cylinder is monitored and subsequently analyzed to obtain the thermal resistance of the film and the film/aluminum interfaces. At least four layers of film are added sequentially to establish a relationship between thermal resistance and film thickness, from which the film thermal conductivity can be determined because compensation can then be made for the film/aluminum interface resistances. Pressure is applied to the "stacks" to minimize interface thermal resistances.
Guarded Heat Flow: Dynatech C-Matic Thermal Conductance Tester Model TCHM-DV (ASTM F433)
The sample is placed between two copper-surfaced plates controlled at different temperatures Surrounding the sample is a guard heater maintained at or near the mean sample temperature to minimize lateral heat transfer. The heat flux between the two plates is measured with a heat flux transducer attached to one of the plates. The overall temperature difference between the two plates surfaces is measured with built-in thermocouples. To reduce thermal resistance of the film/plate interfaces, a thin layer of a commercially available heat sink compound (such as Dow Corning 340) is usually applied to the sample and the test is run under external pressure. Knowing the sample thickness, the plate surface temperatures, the measured heat flux and the contact thermal resistance, the thermal conductivity of the sample can be determined.
Guarded Heat Flow: Thin Material
The Dynatech C-Matic tester is not particularly suited for very thin materials (i.e. with thicknesses less than 0.040"). Therefore, a guarded heat flow method and apparatus to measure through-the-thickness thermal conductivities of thin films has been developed.
The device consists of two copper rods, approximately 1" in diameter and 2" in length. Embedded along the length of each rod are two thermocouples, spaced 1" apart. The rods are wrapped in fiberglass insulation to prevent lateral heat loss. The film sample, coated with "Nujol" mineral oil, is placed between an end of each of the copper rods (which also have a coat of oil) to form a rod/film/rod stack. (The oil is present to ensure good heat transfer between the rods and the film). The stack is positioned between two heated press platens (top platen always hotter than the bottom platen), put under a compressive load to minimize interfacial thermal resistances, and wrapped with another layer of insulation. The stack is allowed to reach equilibrium and the resultant temperature profiles across the copper rods are recorded. The experiment is repeated with different platen set-point temperatures and stack pressures. By monitoring the resultant equilibrium temperature profiles across the copper rods and comparing them to a "standard" material under similar conditions, the thermal conductivity of the film can be calculated.
EXAMPLES Example 1
87.5 grams of Ciba-Geigy hardener HT9679 and 12.5 grams of Ciba-Geigy hardener HT939 were added to a mixture of 60 grams of Dow Chemical "Quatrex" 1010 resin, 160 grams of Dow Chemical "Quatrex" 2010 and 180 grams of Union Carbide ERL-4206 resin. The resulting mixture was stirred until uniform. 40 grams of a three dimensional structure of mesophase pitch based carbon fiber were added to 60 grams of the resulting mixture to form a 40 weight % fiber reinforced epoxy resin. This filled mixture was passed through a 3 roll mill five times and cast onto a 5 mil thick silicone coated polyester film using a spatula. After curing at 160° C. for 1 hour, the filled adhesive film was removed from the polyester film and was polished using 500 and 1200 grit paper.
The polished film was tested for through-the-thickness thermal conductivity using the Guarded Heat Flow: Thin Material method. The thermal conductivity of this adhesive, listed in Table 1, is at least equivalent to those of 79 weight % silver flake filled Ditac® QL® Ribbon adhesives commercially available from Du Pont, yet the weight percent fibers was only 40%.
Example 2
27.5 parts of Union Carbide "UCAR" PKHJ phenoxy resin and 1.7 parts of Union Carbide "UCAR" BRL-2741 resole resin were dissolved in 53.2 parts of methyl ethyl ketone and 17.6 parts of toluene. 22.7 grams of this solution were mixed with 5 grams of a three dimensional structure of mesophase pitch based carbon fiber to yield a uniform dispersion. The filled adhesive resin solution was cast on 2 mil Mylar® film using a 20 mil doctor knife and was dried in an oven at 120° C. for 5 minutes. The Mylar® film was removed and a 4 mil thick, 45 weight % fiber reinforced adhesive film remained. Two 4 mil thick films were laminated together at 150° C. and 200 psi for 15 minutes to form a 6-8 mil thick adhesive film. An unfilled phenoxy/phenol-formaldehyde sample and a 56 weight % fiber reinforced film were prepared in a similar manner.
The three samples were tested for through-the-thickness thermal conductivity using the Guarded Heat Flow: Thin Material method. Test results are given in Table 1 and indicate that the thermal conductivity of the filled adhesives are up to 2× those of 79 weight % silver flake filled Ditac® QL® Ribbon adhesives, yet at fiber loadings only 56% by weight or less.
              TABLE 1                                                     
______________________________________                                    
Thermal Conductivities of Adhesives                                       
Volume %      Weight %  Thermal Conductivity                              
Fibers        Fibers    (BTU in/hr ft.sup.2 °F.)                   
______________________________________                                    
Unfilled Adhesive                                                         
               0        1.318                                             
30            45        6.970                                             
40            56        11.512                                            
              40        9.571                                             
______________________________________
Example 3
A three dimensional structure of mesophase pitch based carbon fiber filled films containing 15, 29 and 39 weight % fibers (10, 20 and 28 volume percent fibers, respectively) were prepared as follows. Three separate dry blends of fibers and K copolyimide powder (representing the three fiber loadings) were prepared by placing the required weights of fiber and powder in polyethylene bags, tying the bags off, and then shaking and mixing the blends to make as uniform a mixture as possible. K copolyimide powder is based on pyromellitic dianhydride and a 70/30 (by weight) mixture of 1,3-bis(3-aminophenoxy)benzene and 2-phenyl-1, 4-bis(4-aminophenoxy))benzene. Approximately 600 grams of each blend were prepared.
Approximately 150-200 grams of a blend were spread out between two cover sheets of Kapton® polyimide film on a belt and the "sandwich" was run through a continuous belt press with heated platens (345° C.). The cover sheets were removed and a fiber filled film remained. When one blend was completed and several pieces of film made, the procedure was repeated for the remaining two blends.
After this initial pass through the press (at a belt speed of 5 feet/minute), the pieces of film were run through the press two more times (with Kapton® cover sheets which were then removed) but at a speed of 1 foot/minute to further reduce film thickness. The resulting films were approximately 3-4 feet long, 6-8 inches wide, 10-19 mils thick.
Unreinforced films were made similarly. The resulting films were approximately 45 feet long, 10 inches wide, 8-14 mils thick.
Pieces of the films were tested for in-plane tensile properties and coefficients of thermal expansions, as well as through-the-thickness thermal conductivities. Because thermal conductivity measurements are made using a variety of techniques and methods, the thermal conductivities were measured via four different methods described herein for comparisons and data validations.
Table 2 gives the results which indicate that the film properties are a function of fiber loading; as fiber loadings increase, both out-of-plane thermal conductivities and tensile moduli increase while in-plane CTE's decrease. The highest loaded film has a uniform CTE (10 ppm/°C.) near that of alumina (6-8 ppm/°C.), a typical "target CTE" electronic packaging material. Compared to Ditac® QL® Ribbon adhesive data, the thermal conductivity and modulus of the highest loaded film are at least equivalent and the CTE is 4× lower than these silver filled adhesives, yet the fiber loading was only 39% by weight.
Example 4
Two identical 2"×2" squares were cut from a circuit board constructed of six layers of Du Pont Pyralux® flexible composites bonded together with Pyralux® LG1002 glass reinforced modified acrylic adhesive. Each layer of flexible composite was constructed with a LF9111 copper-clad laminate coverlayed on both sides with LF0210 coverlay.
Two identical 2"×2" squares were cut from a pitch fiber reinforced metal matrix composite heat sink constructed of 16 layers of 6063 aluminum reinforced with E-120 continuous pitch fibers. The fiber orientation was [0/90]4S and the fiber volume fraction was 35%. One surface of each metal matrix square was scraped with a razor blade and cleaned with solvent to remove all surface contaminants.
One circuit board square was bonded to a heat sink square using Hysol Aerospace & Industrial Products Division Epoxi-patch clear 0151 two part epoxy adhesive by brushing a well stirred mix on the clean metal surface, placing the circuit board on the adhesive, and curing the laminated sample under minimum (<25 psi) pressure. The other squares were bonded to each other with the same base adhesive but the adhesive had been filled with 25 weight percent of a three-dimensional structure of mesophase pitch based carbon fiber blended in as the two part epoxy was mixed.
Both samples were tested for through-the-thickness system thermal conductivities using the Guarded Heat Flow: Dynatech C-Matic Thermal Conductance Tester method. The system thermal conductivity of the sample having the filled adhesive was 3.398 (BTU)(in)/(hr)(ft2)(°F.) vs. 2.705 (BTU)(in)/(hr)(ft2)(°F.) for the sample having the unfilled adhesive, a 26% improvement.
                                  TABLE 2                                 
__________________________________________________________________________
             CTE  CTE Thermal                                             
                             Thermal                                      
                                    Thermal                               
                                           Thermal Tensile                
                                                         Tensile ##       
Volume                                                                    
     Weight                                                               
         Den-                                                             
             (MD) (TD)                                                    
                      Conduc-                                             
                             Conduc-                                      
                                    Conduc-                               
                                           Conduc- Modulus                
                                                         Modulus          
%    %   sity #                                                           
             (ppm/                                                        
                  (ppm/                                                   
                      tivity* (Btu                                        
                             tivity** (Btu                                
                                    tivity tivity  (MD)u (TD)             
Fibers                                                                    
     Fibers                                                               
         (g/cc)                                                           
             °C.)                                                  
                  °C.)                                             
                      in/hr ft.sup.2 °F.)                          
                             in/hr ft.sup.2 °F.)                   
                                    in/hr ft.sup.2 °F.)            
                                           in/hr ft.sup.2                 
                                                   (Kpsi)e.F.)            
                                                         (Kpsi)           
__________________________________________________________________________
Unfilled                                                                  
      0  1.31                                                             
             46   44  1.248  1.179  1.179  0.902   494   487              
Film                                                                      
10   15  1.43                                                             
             22   36  1.387         2.497  2.705   756   687              
20   29  1.49                                                             
             20   19  3.260         4.022  3.745   1293  1045             
28   39  1.56                                                             
             10   10  3.329  5.791  9.016          1212  1117             
__________________________________________________________________________
 NOTES:                                                                   
 Fiber volumes are ±3%.                                                
 CTE values were determined with a Perkin Elmer TMA using an "extension"  
 probe and a 5 gram force. They are representative of the temperature rang
 25-175° C.                                                        
  MD = Machine Direction and TD = Tranverse Direction (both inplane)      
 # ASTM D792                                                              
 ## ASTM D638                                                             
 *ASTM F433 (Dynatech CMatic Guarded Heat Flow method), 50°C.,     
 throughthe-thickness measurement.                                        
 **Guarded Heat Flow:Thin Material method, 90° C.,                 
 throughthe-thickness measurement.                                        
   Laser Flash method, 25° C., throughthe-thickness measurement (by
 University of Delaware).                                                 
    Thick-Film Integrator method, 25° C., throughthe-thickness     
 measurement (by University of Delaware).

Claims (10)

What is claimed is:
1. A thermally conductive adhesive material comprising an adhesive resin filled with from about 20 to about 60 weight percent of a three-dimensional structure of pitch based carbon fibers.
2. The thermally conductive adhesive material of claim 1 wherein said material is in the form of a film.
3. The thermally conductive adhesive material of claim 1 wherein said material is in the form of a film.
4. The adhesive material of claim 1 wherein said adhesive resin is selected from the group consisting of thermoplastic, thermosetting, elastomeric or combinations thereof.
5. The adhesive material of claim 1, said material having a thermal conductivity in the range of from about 6 to about 12 (BTU)(in)/(hr)(ft2)(°F.).
6. The adhesive material of claim 1 wherein said adhesive resin is a thermosetting resin.
7. The adhesive material of claim 6 wherein said pitch based carbon fibers are mesophase pitch.
8. An electronic system having component parts bonded by a layer of adhesive resin filled with from about 20 to about 60 weight % of a three-dimensional structure of pitch based carbon fibers.
9. The system of claim 8 wherein said adhesive material is selected form the group consisting of thermoplastic, thermosetting, elastomeric and combinations thereof.
10. The system of claim 9 wherein said adhesive resin is a thermosetting resin.
US07/520,286 1990-05-07 1990-05-07 Thermally conductive adhesive Expired - Fee Related US5026748A (en)

Priority Applications (15)

Application Number Priority Date Filing Date Title
US07/520,286 US5026748A (en) 1990-05-07 1990-05-07 Thermally conductive adhesive
IL9795791A IL97957A (en) 1990-05-07 1991-04-25 Thermally conductive adhesive
AU76137/91A AU629157B2 (en) 1990-05-07 1991-04-29 Thermally conductive adhesive
JP3128213A JPH06212137A (en) 1990-05-07 1991-05-02 Thermally conductive adhesive material
DE69113108T DE69113108T2 (en) 1990-05-07 1991-05-03 Electronic system containing components that are connected by a thermally conductive adhesive.
EP91304030A EP0456428B1 (en) 1990-05-07 1991-05-03 Electronic system having component parts bonded by a thermally conductive adhesive
CA002041807A CA2041807A1 (en) 1990-05-07 1991-05-03 Thermally conductive adhesive
ES91304030T ES2078443T3 (en) 1990-05-07 1991-05-03 ELECTRONIC SYSTEM WITH COMPONENT PARTS UNITED BY A THERMALLY CONDUCTIVE ADHESIVE.
AT91304030T ATE128168T1 (en) 1990-05-07 1991-05-03 ELECTRONIC SYSTEM CONTAINING COMPONENTS CONNECTED BY A THERMALLY CONDUCTIVE ADHESIVE.
MX025667A MX172824B (en) 1990-05-07 1991-05-06 THERMALLY CONDUCTIVE ADHESIVE MATERIAL
TR91/0473A TR25806A (en) 1990-05-07 1991-05-06 THERMAL CONDUCTIVITY ADHESIVE.
SU914895345A RU2052483C1 (en) 1990-05-07 1991-05-06 Heat-conducting adhesive
KR1019910007335A KR910020139A (en) 1990-05-07 1991-05-07 Thermal conductive adhesive
CN91103592A CN1041743C (en) 1990-05-07 1991-05-07 Thermally conductive adhesive
BR919101849A BR9101849A (en) 1990-05-07 1991-05-07 THERMAL CONDUCTIVE ADHESIVE

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US07/520,286 US5026748A (en) 1990-05-07 1990-05-07 Thermally conductive adhesive

Publications (1)

Publication Number Publication Date
US5026748A true US5026748A (en) 1991-06-25

Family

ID=24071950

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/520,286 Expired - Fee Related US5026748A (en) 1990-05-07 1990-05-07 Thermally conductive adhesive

Country Status (15)

Country Link
US (1) US5026748A (en)
EP (1) EP0456428B1 (en)
JP (1) JPH06212137A (en)
KR (1) KR910020139A (en)
CN (1) CN1041743C (en)
AT (1) ATE128168T1 (en)
AU (1) AU629157B2 (en)
BR (1) BR9101849A (en)
CA (1) CA2041807A1 (en)
DE (1) DE69113108T2 (en)
ES (1) ES2078443T3 (en)
IL (1) IL97957A (en)
MX (1) MX172824B (en)
RU (1) RU2052483C1 (en)
TR (1) TR25806A (en)

Cited By (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USH1332H (en) 1988-10-03 1994-07-05 E. I. Du Pont De Nemours And Company Thermal conductive material
US5695847A (en) * 1996-07-10 1997-12-09 Browne; James M. Thermally conductive joining film
WO1998040431A1 (en) * 1997-03-11 1998-09-17 Amoco Corporation Thermally conductive film and method for the preparation thereof
US5907273A (en) * 1993-11-24 1999-05-25 Rochester Gauges, Inc. Linear positioning indicator
US5930117A (en) * 1996-05-07 1999-07-27 Sheldahl, Inc. Heat sink structure comprising a microarray of thermal metal heat channels or vias in a polymeric or film layer
US6084299A (en) * 1995-11-09 2000-07-04 International Business Machines Corporation Integrated circuit package including a heat sink and an adhesive
US6392309B1 (en) * 1995-08-25 2002-05-21 Sony Corporation Semiconductor device including solid state imaging device
US6402866B1 (en) 1999-09-30 2002-06-11 International Business Machines Corporation Powdered metallic sheet method for deposition of substrate conductors
US20030174455A1 (en) * 2002-03-15 2003-09-18 Vijay Kataria Thermal dissipation assembly for electronic components
US6644849B1 (en) * 1999-09-20 2003-11-11 Honeywell International, Inc. Low precision temperature sensor for aircraft applications
US20040060691A1 (en) * 2001-06-28 2004-04-01 Intel Corporation Short carbon fiber enhanced thermal grease
US20050045855A1 (en) * 2003-09-03 2005-03-03 Tonapi Sandeep Shrikant Thermal conductive material utilizing electrically conductive nanoparticles
US20050136248A1 (en) * 2003-12-23 2005-06-23 Charles Leu Thermal interface material and method for manufacturing same
US20060055077A1 (en) * 2003-11-14 2006-03-16 Heikkila Kurt E Extrusion method forming an enhanced property metal polymer composite
US20060197222A1 (en) * 2003-07-31 2006-09-07 Franz Auerbach Arrangement of an electrical component placed on a substrate, and method for producing the same
US20080226239A1 (en) * 2007-03-14 2008-09-18 Sumitomo Electric Industries, Ltd. Optical transceiver with mechanism to dissipate heat efficiently without affecting optical coupling condition
US20090034915A1 (en) * 2007-07-31 2009-02-05 Sumitomo Electric Industries, Ltd. Optical transceiver with an optical sub-assembly supporter by a holder and a cover
US20090127801A1 (en) * 2003-11-14 2009-05-21 Wild River Consulting Group, Llc Enhanced property metal polymer composite
US20090250655A1 (en) * 2006-07-28 2009-10-08 Teijin Limited Heat-conductive adhesive
US20090298976A1 (en) * 2005-10-26 2009-12-03 Hiroyuki Yano Fiber-Reinforced Composition Resin Composition, Adhesive and Sealant
US20090314482A1 (en) * 2006-02-09 2009-12-24 Wild River Consulting Group, Llc Metal polymer composite with enhanced viscoelastic and thermal properties
US20100265665A1 (en) * 2009-04-15 2010-10-21 Yukihiro Kozaka Electronic device having a heat sink
US20110198067A1 (en) * 2006-06-08 2011-08-18 International Business Machines Corporation Sheet having high thermal conductivity and flexibility
US20110236699A1 (en) * 2003-11-14 2011-09-29 Tundra Composites, LLC Work piece comprising metal polymer composite with metal insert
CN102130078B (en) * 2010-01-20 2013-03-13 财团法人工业技术研究院 Heat-conducting insulated composite film and chip stacking structures
US8487034B2 (en) 2008-01-18 2013-07-16 Tundra Composites, LLC Melt molding polymer composite and method of making and using the same
US8841358B2 (en) 2009-04-29 2014-09-23 Tundra Composites, LLC Ceramic composite
US9105382B2 (en) 2003-11-14 2015-08-11 Tundra Composites, LLC Magnetic composite
US9331257B2 (en) 2011-01-26 2016-05-03 Emitec Gesellschaft Fuer Emissionstechnologie Mbh Thermoelectric module with a heat conducting layer and method of manufacturing a thermoelectric module
CN105810595A (en) * 2015-01-21 2016-07-27 英飞凌科技股份有限公司 Method for handling a product substrate, a bonded substrate system and a temporary adhesive
US10633559B2 (en) 2009-12-21 2020-04-28 Tesa Se Heat-activated, glueable surface elements

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2880875B2 (en) * 1993-04-12 1999-04-12 日本電気株式会社 Adhesive for electronic devices
JP2000281995A (en) * 1999-03-30 2000-10-10 Polymatech Co Ltd Thermally conductive adhesive film and semiconductor device
JP3720044B1 (en) * 2005-03-22 2005-11-24 株式会社物産ナノテク研究所 Composite material
US8729398B2 (en) * 2012-03-28 2014-05-20 Deere & Company Electrical assembly with compliant pins for heat dissipation
WO2014010520A1 (en) * 2012-07-07 2014-01-16 デクセリアルズ株式会社 Thermally conductive sheet
EP3479662B1 (en) 2016-06-29 2023-03-01 At&S Austria Technologie & Systemtechnik Aktiengesellschaft Cooling component carrier material by carbon structure within dielectric shell
CN109788635B (en) * 2019-03-15 2020-04-21 深圳市满坤电子有限公司 Processing method of printed circuit board

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4522771A (en) * 1982-10-21 1985-06-11 General Electric Company Method of fabricating layer insulation for use in high-voltage electrical equipment
US4609586A (en) * 1984-08-02 1986-09-02 The Boeing Company Thermally conductive printed wiring board laminate
US4689110A (en) * 1983-12-22 1987-08-25 Trw Inc. Method of fabricating multilayer printed circuit board structure
US4791076A (en) * 1984-08-02 1988-12-13 Hughes Aircraft Company Graphite fiber reinforced silica matrix composite
US4861653A (en) * 1987-09-02 1989-08-29 E. I. Du Pont De Nemours And Company Pitch carbon fibers and batts

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0240274B2 (en) * 1984-12-14 1990-09-11 Yokohama Rubber Co Ltd DODENSEINETSUKOKAGATASETSUCHAKUSOSEIBUTSU
JPH0623350B2 (en) * 1988-01-20 1994-03-30 信越ポリマー株式会社 Anisotropic conductive adhesive
JPH02198114A (en) * 1988-10-03 1990-08-06 E I Du Pont De Nemours & Co Product
BR8905015A (en) * 1988-10-03 1990-05-08 Du Pont THERMAL CONDUCTIVE MATERIAL
JPH0375851A (en) * 1989-08-17 1991-03-29 Nec Corp Information processor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4522771A (en) * 1982-10-21 1985-06-11 General Electric Company Method of fabricating layer insulation for use in high-voltage electrical equipment
US4689110A (en) * 1983-12-22 1987-08-25 Trw Inc. Method of fabricating multilayer printed circuit board structure
US4609586A (en) * 1984-08-02 1986-09-02 The Boeing Company Thermally conductive printed wiring board laminate
US4791076A (en) * 1984-08-02 1988-12-13 Hughes Aircraft Company Graphite fiber reinforced silica matrix composite
US4861653A (en) * 1987-09-02 1989-08-29 E. I. Du Pont De Nemours And Company Pitch carbon fibers and batts

Cited By (52)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USH1332H (en) 1988-10-03 1994-07-05 E. I. Du Pont De Nemours And Company Thermal conductive material
US5907273A (en) * 1993-11-24 1999-05-25 Rochester Gauges, Inc. Linear positioning indicator
US6392309B1 (en) * 1995-08-25 2002-05-21 Sony Corporation Semiconductor device including solid state imaging device
US6084299A (en) * 1995-11-09 2000-07-04 International Business Machines Corporation Integrated circuit package including a heat sink and an adhesive
US6226187B1 (en) 1995-11-09 2001-05-01 International Business Machines Corporation Integrated circuit package
US5930117A (en) * 1996-05-07 1999-07-27 Sheldahl, Inc. Heat sink structure comprising a microarray of thermal metal heat channels or vias in a polymeric or film layer
US5849130A (en) * 1996-07-10 1998-12-15 Browne; James M. Method of making and using thermally conductive joining film
US6014999A (en) * 1996-07-10 2000-01-18 Browne; James M. Apparatus for making thermally conductive film
US5695847A (en) * 1996-07-10 1997-12-09 Browne; James M. Thermally conductive joining film
WO1998040431A1 (en) * 1997-03-11 1998-09-17 Amoco Corporation Thermally conductive film and method for the preparation thereof
US6644849B1 (en) * 1999-09-20 2003-11-11 Honeywell International, Inc. Low precision temperature sensor for aircraft applications
US6402866B1 (en) 1999-09-30 2002-06-11 International Business Machines Corporation Powdered metallic sheet method for deposition of substrate conductors
US20040060691A1 (en) * 2001-06-28 2004-04-01 Intel Corporation Short carbon fiber enhanced thermal grease
US6804118B2 (en) * 2002-03-15 2004-10-12 Delphi Technologies, Inc. Thermal dissipation assembly for electronic components
US20030174455A1 (en) * 2002-03-15 2003-09-18 Vijay Kataria Thermal dissipation assembly for electronic components
US7649272B2 (en) 2003-07-31 2010-01-19 Siemens Aktiengesellschaft Arrangement of an electrical component placed on a substrate, and method for producing the same
US20060197222A1 (en) * 2003-07-31 2006-09-07 Franz Auerbach Arrangement of an electrical component placed on a substrate, and method for producing the same
US7550097B2 (en) 2003-09-03 2009-06-23 Momentive Performance Materials, Inc. Thermal conductive material utilizing electrically conductive nanoparticles
US20050045855A1 (en) * 2003-09-03 2005-03-03 Tonapi Sandeep Shrikant Thermal conductive material utilizing electrically conductive nanoparticles
US7491356B2 (en) 2003-11-14 2009-02-17 Tundra Composites Llc Extrusion method forming an enhanced property metal polymer composite
US9105382B2 (en) 2003-11-14 2015-08-11 Tundra Composites, LLC Magnetic composite
US20090127801A1 (en) * 2003-11-14 2009-05-21 Wild River Consulting Group, Llc Enhanced property metal polymer composite
US20060055077A1 (en) * 2003-11-14 2006-03-16 Heikkila Kurt E Extrusion method forming an enhanced property metal polymer composite
US20110236699A1 (en) * 2003-11-14 2011-09-29 Tundra Composites, LLC Work piece comprising metal polymer composite with metal insert
US7183003B2 (en) * 2003-12-23 2007-02-27 Hon Hai Precision Ind. Co., Ltd Thermal interface material and method for manufacturing same
US20050136248A1 (en) * 2003-12-23 2005-06-23 Charles Leu Thermal interface material and method for manufacturing same
US20090298976A1 (en) * 2005-10-26 2009-12-03 Hiroyuki Yano Fiber-Reinforced Composition Resin Composition, Adhesive and Sealant
US20090314482A1 (en) * 2006-02-09 2009-12-24 Wild River Consulting Group, Llc Metal polymer composite with enhanced viscoelastic and thermal properties
US9179579B2 (en) * 2006-06-08 2015-11-03 International Business Machines Corporation Sheet having high thermal conductivity and flexibility
US20110198067A1 (en) * 2006-06-08 2011-08-18 International Business Machines Corporation Sheet having high thermal conductivity and flexibility
US20090250655A1 (en) * 2006-07-28 2009-10-08 Teijin Limited Heat-conductive adhesive
US8017674B2 (en) * 2006-07-28 2011-09-13 Teijin Limited Heat-conductive adhesive
US20080226239A1 (en) * 2007-03-14 2008-09-18 Sumitomo Electric Industries, Ltd. Optical transceiver with mechanism to dissipate heat efficiently without affecting optical coupling condition
US20090034915A1 (en) * 2007-07-31 2009-02-05 Sumitomo Electric Industries, Ltd. Optical transceiver with an optical sub-assembly supporter by a holder and a cover
US7621679B2 (en) 2007-07-31 2009-11-24 Sumitomo Electric Industries, Ltd. Optical transceiver with an optical sub-assembly supporter by a holder and a cover
US8487034B2 (en) 2008-01-18 2013-07-16 Tundra Composites, LLC Melt molding polymer composite and method of making and using the same
US9153377B2 (en) 2008-01-18 2015-10-06 Tundra Composites, LLC Magnetic polymer composite
US20100265665A1 (en) * 2009-04-15 2010-10-21 Yukihiro Kozaka Electronic device having a heat sink
US8841358B2 (en) 2009-04-29 2014-09-23 Tundra Composites, LLC Ceramic composite
US10508187B2 (en) 2009-04-29 2019-12-17 Tundra Composites, LLC Inorganic material composite
US9249283B2 (en) 2009-04-29 2016-02-02 Tundra Composites, LLC Reduced density glass bubble polymer composite
US9376552B2 (en) 2009-04-29 2016-06-28 Tundra Composites, LLC Ceramic composite
US11767409B2 (en) 2009-04-29 2023-09-26 Tundra Composites, LLC Reduced density hollow glass microsphere polymer composite
US9771463B2 (en) 2009-04-29 2017-09-26 Tundra Composites, LLC Reduced density hollow glass microsphere polymer composite
US11041060B2 (en) 2009-04-29 2021-06-22 Tundra Composites, LLC Inorganic material composite
US10633559B2 (en) 2009-12-21 2020-04-28 Tesa Se Heat-activated, glueable surface elements
CN102130078B (en) * 2010-01-20 2013-03-13 财团法人工业技术研究院 Heat-conducting insulated composite film and chip stacking structures
US9331257B2 (en) 2011-01-26 2016-05-03 Emitec Gesellschaft Fuer Emissionstechnologie Mbh Thermoelectric module with a heat conducting layer and method of manufacturing a thermoelectric module
US10600690B2 (en) 2015-01-21 2020-03-24 Infineon Technologies Ag Method for handling a product substrate and a bonded substrate system
CN105810595B (en) * 2015-01-21 2019-01-22 英飞凌科技股份有限公司 For handling the method, the substrate system of bonding and temporary adhesive of product substrate
US10056295B2 (en) 2015-01-21 2018-08-21 Infineon Technologies Ag Method for handling a product substrate, a bonded substrate system and a temporary adhesive
CN105810595A (en) * 2015-01-21 2016-07-27 英飞凌科技股份有限公司 Method for handling a product substrate, a bonded substrate system and a temporary adhesive

Also Published As

Publication number Publication date
JPH06212137A (en) 1994-08-02
CN1041743C (en) 1999-01-20
EP0456428A3 (en) 1992-02-26
EP0456428A2 (en) 1991-11-13
KR910020139A (en) 1991-12-19
CN1057282A (en) 1991-12-25
BR9101849A (en) 1991-12-17
DE69113108D1 (en) 1995-10-26
TR25806A (en) 1993-09-01
RU2052483C1 (en) 1996-01-20
CA2041807A1 (en) 1991-11-08
IL97957A (en) 1994-04-12
ATE128168T1 (en) 1995-10-15
EP0456428B1 (en) 1995-09-20
MX172824B (en) 1994-01-14
AU629157B2 (en) 1992-09-24
IL97957A0 (en) 1992-06-21
DE69113108T2 (en) 1996-05-09
AU7613791A (en) 1991-11-07
ES2078443T3 (en) 1995-12-16

Similar Documents

Publication Publication Date Title
US5026748A (en) Thermally conductive adhesive
US5677045A (en) Laminate and multilayer printed circuit board
EP0257466B1 (en) Low thermal expansion,heat conducting laminates having layersof metal and reinforced polymer matrix composite
EP0957664B1 (en) Resin-carrying metal foil for multilayered wiring board, process for manufacturing the same, multilayered wiring board, and electronic device
EP0309982A2 (en) Polymer-ceramic composite plies
US6649325B1 (en) Thermally conductive dielectric mounts for printed circuitry and semi-conductor devices and method of preparation
Brownlee et al. Liquid crystal polymers (LCP) for high performance SOP applications
EP0642919B1 (en) Laminate and multilayer printed circuit board
Li et al. An improvement of thermal conductivity of underfill materials for flip-chip packages
US5254412A (en) Heat resisting adhesive material
Bujard et al. Thermally conductive aluminium nitride-filled epoxy resin (for electronic packaging)
WO1998040431A1 (en) Thermally conductive film and method for the preparation thereof
US5270371A (en) Adhesive compositions for electronic packages
JP4192871B2 (en) Laminated board and wiring board
WO1993024314A1 (en) Thermally conductive printed circuit board
WO1996011105A1 (en) Thermal management for additive printed circuits
TWI799128B (en) Metal clad substrate
CN110103537A (en) A kind of high thermal conductivity copper-clad laminate
Asai et al. Design and characteristics of a newly developed cavity-up plastic and ceramic laminated thin BGA package
JP4192870B2 (en) Laminated board and wiring board
CN114867185B (en) Carrier plate for heat dissipation high-frequency IC packaging and preparation process thereof
Kowbel et al. Low cost, high thermal conductivity composite heat spreaders for power electronics
Gallagher et al. Materials selection issues for high operating temperature (HOT) electronic packaging
JP2001523047A (en) Non-conductive heat dissipator components
Tain et al. Thermal Material for PCB Substrate and Its Measurement Method

Legal Events

Date Code Title Description
AS Assignment

Owner name: E. I. DU PONT DE NEMOURS AND COMPANY, WILMINGTON,

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:ADAMS, JEROME T.;YOST, BRUCE A.;REEL/FRAME:005437/0804

Effective date: 19900501

CC Certificate of correction
FPAY Fee payment

Year of fee payment: 4

AS Assignment

Owner name: FIBERITE, INC., A DELAWARE CORPORATION, ARIZONA

Free format text: ;ASSIGNOR:E.I. DU PONT DE NEMOURS AND COMPANY;REEL/FRAME:008613/0877

Effective date: 19970404

Owner name: FIBERITE, INC., A DELAWARE CORP., ARIZONA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:E.I. DU PONT DE NEMOURS AND COMPANY, A DELAWARE CORP.;REEL/FRAME:008621/0594

Effective date: 19970404

FPAY Fee payment

Year of fee payment: 8

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20030625